[PATCH 6/9] [media] vp702x: fix locking of usb operations

From: Florian Mickler
Date: Mon Mar 21 2011 - 06:19:53 EST


Otherwise it is not obvious that vp702x_usb_in_op or vp702x_usb_out_op
will not interfere with any vp702x_usb_inout_op.

Note: This change is tested to compile only, as I don't have the
hardware.

Signed-off-by: Florian Mickler <florian@xxxxxxxxxxx>
---
drivers/media/dvb/dvb-usb/vp702x.c | 37 +++++++++++++++++++++++++++++------
1 files changed, 30 insertions(+), 7 deletions(-)

diff --git a/drivers/media/dvb/dvb-usb/vp702x.c b/drivers/media/dvb/dvb-usb/vp702x.c
index 35fe778..c82cb6b 100644
--- a/drivers/media/dvb/dvb-usb/vp702x.c
+++ b/drivers/media/dvb/dvb-usb/vp702x.c
@@ -30,8 +30,8 @@ struct vp702x_adapter_state {
u8 pid_filter_state;
};

-/* check for mutex FIXME */
-int vp702x_usb_in_op(struct dvb_usb_device *d, u8 req, u16 value, u16 index, u8 *b, int blen)
+static int vp702x_usb_in_op_unlocked(struct dvb_usb_device *d, u8 req,
+ u16 value, u16 index, u8 *b, int blen)
{
int ret;

@@ -55,8 +55,20 @@ int vp702x_usb_in_op(struct dvb_usb_device *d, u8 req, u16 value, u16 index, u8
return ret;
}

-static int vp702x_usb_out_op(struct dvb_usb_device *d, u8 req, u16 value,
- u16 index, u8 *b, int blen)
+int vp702x_usb_in_op(struct dvb_usb_device *d, u8 req, u16 value,
+ u16 index, u8 *b, int blen)
+{
+ int ret;
+
+ mutex_lock(&d->usb_mutex);
+ ret = vp702x_usb_in_op_unlocked(d, req, value, index, b, blen);
+ mutex_unlock(&d->usb_mutex);
+
+ return ret;
+}
+
+int vp702x_usb_out_op_unlocked(struct dvb_usb_device *d, u8 req, u16 value,
+ u16 index, u8 *b, int blen)
{
int ret;
deb_xfer("out: req. %02x, val: %04x, ind: %04x, buffer: ",req,value,index);
@@ -74,6 +86,18 @@ static int vp702x_usb_out_op(struct dvb_usb_device *d, u8 req, u16 value,
return 0;
}

+int vp702x_usb_out_op(struct dvb_usb_device *d, u8 req, u16 value,
+ u16 index, u8 *b, int blen)
+{
+ int ret;
+
+ mutex_lock(&d->usb_mutex);
+ ret = vp702x_usb_out_op_unlocked(d, req, value, index, b, blen);
+ mutex_unlock(&d->usb_mutex);
+
+ return ret;
+}
+
int vp702x_usb_inout_op(struct dvb_usb_device *d, u8 *o, int olen, u8 *i, int ilen, int msec)
{
int ret;
@@ -81,12 +105,11 @@ int vp702x_usb_inout_op(struct dvb_usb_device *d, u8 *o, int olen, u8 *i, int il
if ((ret = mutex_lock_interruptible(&d->usb_mutex)))
return ret;

- ret = vp702x_usb_out_op(d,REQUEST_OUT,0,0,o,olen);
+ ret = vp702x_usb_out_op_unlocked(d, REQUEST_OUT, 0, 0, o, olen);
msleep(msec);
- ret = vp702x_usb_in_op(d,REQUEST_IN,0,0,i,ilen);
+ ret = vp702x_usb_in_op_unlocked(d, REQUEST_IN, 0, 0, i, ilen);

mutex_unlock(&d->usb_mutex);
-
return ret;
}

--
1.7.4.1

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